The closely held plan forwarded by top Pentagon advisers calls for keeping 15 combat brigades in Iraq until the end of the year, according to senior defense officials. It would also send a small Marine contingent to Afghanistan in November to replace one of two units slated to head home then.
Mr. Bush is scheduled to make remarks Tuesday at the National Defense University in Washington. White House press secretary Dana Perino says he has been talking with his national security team and will be consulting with members of Congress about Iraq.
Under the Pentagon recommendations, one combat brigade - numbering between 3,500 to 4,000 troops - will leave Iraq after the first of the year and will not be replaced. In addition, at least one Marine battalion will leave and not be replaced, as well as a few thousand support forces, defense officials said.
Those forces could include military police officers and other support troops that went to Iraq over the past year to support the large military buildup ordered by Mr. Bush in early 2007 to quell the growing violence.
The new plan being reviewed by Mr. Bush may disappoint some Congress members and others who expected a larger, faster reduction of troops in Iraq, considering the significant downturn in violence. According to defense officials, violence has plunged by about 80 percent since last year's peak.
Gen. David Petraeus, the top U.S. commander in Iraq, delivered his recommendations to military leaders about two weeks ago. He had initially argued to maintain the current force levels in Iraq - about 146,000 troops, including 15 combat brigades and thousands of support forces - through June, according to defense officials.
Officials discussed details of the plan on condition of anonymity because Mr. Bush has not yet made a final decision.
"The question on the president's mind has been, 'How do we make sure that we cement those gains and not jeopardize those gains and be able to continue the process of return on success?"' said Perino.
If Mr. Bush adopts the recommendations, it would be left to the next president to execute further troop reductions in Iraq and a greater buildup in Afghanistan. Several more combat brigades are scheduled to leave Iraq during the first half of next year, and decisions must be made on whether or not to replace them.
Commanders have repeatedly asked for more troops in Afghanistan, where there has been a resurgence of the Taliban and a growth in violence.
Mr. Bush's term ends in January. Democratic presidential nominee Barack Obama has advocated pulling all U.S. combat forces out of Iraq within 16 months of the new president taking office. GOP nominee John McCain has said he would rely on the advice of U.S. military commanders to determine the timing and pace of troop reductions. Both candidates have said more troops are needed in Afghanistan.
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